From d54eaaa268eb79a51ac11bfa8bbfb456c0b1a1fa Mon Sep 17 00:00:00 2001
From: Jeff King <peff@peff.net>
Date: Fri, 28 Mar 2008 17:29:01 -0400
Subject: [PATCH] send-email: rfc2047-quote subject lines with non-ascii
 characters

We always use 'utf-8' as the encoding, since we currently
have no way of getting the information from the user.

This also refactors the quoting of recipient names, since
both processes can share the rfc2047 quoting code.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 git-send-email.perl   | 19 +++++++++++++++++--
 t/t9001-send-email.sh | 15 +++++++++++++++
 2 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/git-send-email.perl b/git-send-email.perl
index 71ba44d69..455a57059 100755
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -534,6 +534,14 @@ EOT
 		if (!$in_body && /^MIME-Version:/i) {
 			$need_8bit_cte = 0;
 		}
+		if (!$in_body && /^Subject: ?(.*)/i) {
+			my $subject = $1;
+			$_ = "Subject: " .
+				($subject =~ /[^[:ascii:]]/ ?
+				 quote_rfc2047($subject) :
+				 $subject) .
+				"\n";
+		}
 		print C2 $_;
 	}
 	close(C);
@@ -624,6 +632,14 @@ sub unquote_rfc2047 {
 	return wantarray ? ($_, $encoding) : $_;
 }
 
+sub quote_rfc2047 {
+	local $_ = shift;
+	my $encoding = shift || 'utf-8';
+	s/([^-a-zA-Z0-9!*+\/])/sprintf("=%02X", ord($1))/eg;
+	s/(.*)/=\?$encoding\?q\?$1\?=/;
+	return $_;
+}
+
 # use the simplest quoting being able to handle the recipient
 sub sanitize_address
 {
@@ -641,8 +657,7 @@ sub sanitize_address
 
 	# rfc2047 is needed if a non-ascii char is included
 	if ($recipient_name =~ /[^[:ascii:]]/) {
-		$recipient_name =~ s/([^-a-zA-Z0-9!*+\/])/sprintf("=%02X", ord($1))/eg;
-		$recipient_name =~ s/(.*)/=\?utf-8\?q\?$1\?=/;
+		$recipient_name = quote_rfc2047($recipient_name);
 	}
 
 	# double quotes are needed if specials or CTLs are included
diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
index e222c4932..a4bcd282b 100755
--- a/t/t9001-send-email.sh
+++ b/t/t9001-send-email.sh
@@ -210,4 +210,19 @@ test_expect_success '--compose respects user mime type' '
 	! grep "^Content-Type: text/plain; charset=utf-8" msgtxt1
 '
 
+test_expect_success '--compose adds MIME for utf8 subject' '
+	clean_fake_sendmail &&
+	echo y | \
+	  GIT_EDITOR=$(pwd)/fake-editor \
+	  GIT_SEND_EMAIL_NOTTY=1 \
+	  git send-email \
+	  --compose --subject utf8-sübjëct \
+	  --from="Example <nobody@example.com>" \
+	  --to=nobody@example.com \
+	  --smtp-server="$(pwd)/fake.sendmail" \
+	  $patches &&
+	grep "^fake edit" msgtxt1 &&
+	grep "^Subject: =?utf-8?q?utf8-s=C3=BCbj=C3=ABct?=" msgtxt1
+'
+
 test_done
-- 
2.30.2